Desktop CD Login Credentials?

Hi all. I made a Desktop CD for 32-bit PowerPC from this link. I'm able to get it to boot but it puts me a a logon screen for which I'm unable to login.

I've tried all sorts of combinations: username Ubuntu with Ubuntu password, username Ubuntu with no password, my username and password for the account I was logged in as when I made the CD, no username or password. Just can't seem to find the correct password.